1. Field of the Invention
The present invention is directed to aspects of a barrier assembly protecting the edge of an elevated loading platform or mezzanine, where the loading platform is adapted to receive pallets of articles from an elevated load-in side of the loading platform, and where workers/handlers will remove the articles from a handling side of the loading platform. In particular, the barrier assembly provides a protective barrier on the load-in side of the loading platform when workers are removing articles from the handling side of the platform and also provides a barrier on the handling side of the loading platform when the articles are being loaded onto the platform by forklift trucks through the load-in side of the platform.
2. Description of the Related Art
A typical distribution center or warehouse may include a plurality of elevated loading platforms or mezzanines that have openings on the load-in side of the loading platforms for receiving pallets of articles from forklift trucks, and that also have openings on the handling side of the loading platforms for facilitating removal of the loaded articles by workers. Even though the workers will typically remain clear from the load-in side of the loading platform while removing the articles therefrom, the openings from the load-in side of the loading platforms for receiving the pallets from the forklift trucks present a potential fall hazard for the workers. Furthermore, even though workers will typically remain clear from the loading platform while pallets are being loaded onto the platform by forklift trucks, openings into the loading platform during this operation present a potential fall hazard for the workers as well as a potential for injuries caused by the loading articles.
U.S. Pat. No. 4,422,264 discloses a safety gate assembly that includes first and second safety gates, each of which have rollers that are received within a pair of parallel, inverted U-shaped tracks. The safety gates are coupled together by cables, which are guided between the gates by pulleys positioned above the gates. When one of the safety gates is lifted (providing access to one side of the preselected area) the pulley assembly will operate so as to allow the second safety gate to be lowered into a position blocking entrance to the opposite side of the preselected area. Likewise, when the second safety gate is lifted so as to allow entrance to the preselected area, the cable and pulley assembly will operate so as to allow the first safety gate to be lowered again, thereby restricting entrance to the preselected area from its opposite position.
U.S. Pat. No. 6,212,826, owned by the assignee of the present invention, discloses a safety assembly that includes a pair of parallel guide rails, each shaped generally as an inverted U; a first gate segment having at least one pair of rollers positioned on opposite lateral sides thereof, where each roller is received within a respective one of the guide rails so that the first gate segment is guided by the pair of guide rails; a second gate segment having at least one pair of rollers positioned on opposite lateral sides thereof, where each roller is received within a respective one of the guide rails so that the second gate segment is guided by the pair of guide rails; and at least one substantially rigid cross-bar pivotally connected between the first and second gate segments. The first gate segment is guided by the guide rails from a first barrier position in which it is positioned entirely within the front vertical portions of the guide rails to an open position in which it is positioned at least partially in the horizontal portion of the guide rails; and the second gate segment is guided by the guide rails from a second barrier position in which it is positioned entirely within the back vertical portions of the guide rails to an open position in which it is positioned at least partially in the horizontal portion of the guide rails. The cross-bar has a length which requires that when the first gate segment is in its barrier position the second gate segment will be in its open position, and vice-versa. Therefore, because the cross-bar is substantially rigid, it will restrict the first and second gate segments from being lifted simultaneously to their open positions.